Method and a computer for handling operational data of wind power plants

ABSTRACT

Example embodiments of the present invention relate to a method for collecting data from a wind turbine plant, where data are collected regularly. The collected data made can be stored, where corrections are performed on the stored data. The method also maintains or stores the originally collected data, so that reports may be generated to represent selected data in a plurality of different types of reports. Accordingly, a wind turbine plant may be controlled in relation to originally collected data and in relation to possible correction made to the data.

The present invention relates to a method and a computer system forreceiving and handling operational data from a plurality of windturbines within a confined area forming a wind power plant.

BACKGROUND OF THE INVENTION

Data from wind power plants are received by a central computer systemfrom the plurality of wind turbines forming the wind power plant as wellas from other parts, such as wind anemometers, power output meters etc.with the purpose of surveying the performance and operation of the powerplant and for producing reports of the performance. The latter isimportant as the contracts between manufactures and owners of the powerplant usually are based on a set of performance parameters that areevaluated from such reports. The wind turbines report their operationalparameters, e.g. power production, pitch angle of the blades, localmeasured wind speed and direction, temperatures of the generator, powertransformer etc., angle of yaw, as well as the operational status, i.e.the categorisation of the time period of the data, such as “normaloperation”, “yawing”, “turning of nacelle to recoil cables”, “no contactwith power grid”, failures of different types etc. In particular, theoperational status is important for non-productive periods, so-calleddowntime because the amount of downtime due to failure of the windturbines is a significant parameter in computing the performance of thewind power plant. The reporting from the wind turbines is maderegularly, typical every 10 minutes, and these data are called raw data.

The quality and completeness of the raw data is normally notsatisfactory for direct generation of reports and manipulation of theraw data is performed by overwriting the raw data with corrected data toestimate missing data, correct erroneous data, e.g. values being out ofa reasonable range or categorisation data, in particular downtime due tospecific causes externally to the power plant. This correction of theraw data is performed as a series of automated routines each correctingfor different faults according to a specific method, supplied with anumber of manually generated corrections. Thus, the final data fromwhich the reports are generated may typically comprise a considerableamount of data that have been added, altered or corrected one or severaltimes.

Although a copy of the raw data usually is saved as a separate databasefile, the history of corrections is normally lost and the relationbetween the measured data and the corrected data may only be resolved bycomparing the final data with the raw data.

It has been found by the present inventors that it is advantageous to beable to provide a more detailed substantiation of the corrections madeto the raw data in order to generate the performance reports so that thecredibility of the report can be estimated. Furthermore, it has alsobeen found to be advantageous to facilitate the generation of differentreports in order to evaluate different aspects of the performance andoperation of the wind power plant, e.g. for optimisation of differentaspects of the operational parameters, for identifying the importance ofvarious reasons for downtime and for evaluation of the plant performanceaccording to a set of contractual rules.

A separate log of the corrections may be kept and a backtracking of eachof the final data by means of the log may be applied to generate each ofthe different reports and the substantiation of the corrections.However, this procedure is tedious and requires many calculations anddatabase lookups, particularly for the large amounts of data originatingfrom large wind power plants over long time periods of several months oreven years. The request for generation of different reports based ondifferent corrections or priority of the corrections may necessitatethat a separate series of corrections starting from the raw data isperformed for each of the reports.

SUMMARY OF THE INVENTION

Thus, the objective problem to be solved by the present invention is toprovide a method and a computer system for collecting raw data from aplurality of units, including a plurality of wind turbines, of a windpower plant, correcting the raw data with a plurality of routines andgenerating a plurality of reports, in which said generation of theplurality of reports based on different combinations of said correctingroutines is facilitated.

This problem is solved by means of the present invention by preservingall the collected, raw data as well as all automatically generated andmanually generated correction data in the same data structure, typicallya two-dimensional matrix for each turbine, in which each columnrepresents a data type, such as, e.g., time, measured production,reported operational status, production estimated from wind speed,production estimated from neighbouring wind turbines, automaticallycorrected operational status, manually corrected operational status,etc. and each row represents a period of a length, typically 10 minutes,occurring at a specified time and date. The data structure may also be,or be regarded as, a three-dimensional structure of which the twodimensions are as described and the third dimension represents theplurality of wind turbines so that each wind turbine has onetwo-dimensional data layer for its own data.

This solution requires much larger data storage means that the knownsolutions, but it is thereby achieved that all different kinds ofrequested reports may easily be generated from the data, for whichreports the priority of selecting data on which to base the report isdiverging, e.g. whether to use the production estimated from wind speedor the production estimated from neighbouring wind turbines if theoperational data for a wind turbine are missing for a period.Furthermore, it is easy to substantiate the type and amount ofcorrections on which a given report is based.

Example embodiments of the present invention provide a method ofcollecting and correcting operational data from a wind power plant by acomputer device, comprising the steps of

regularly receiving operational data from a plurality of wind turbine ofsaid wind power plant,

storing said operational data in a dedicated part of a dimensionallyordered data structure in a data storage device associated with thecomputer device,

performing a plurality of predefined correction routines each producinga set of correction data,

storing said sets of correction data in thereto dedicated parts of saiddata structure in said data storage means so that all previous storeddata are preserved, and

generating reports of a plurality of types, each type having apredefined set of rules for selecting data from said stored data onwhich selected data the report type is based.

By the term “dimensionally ordered data structure” is understood e.g. atwo-dimensional matrix of data, of which the rows represent periods andthe columns represent data, or a three-dimensional matrix of data, ofwhich the third dimension represents the plurality of wind turbines sothat each turbine has its dedicated two-dimensional data layer. Moredimensions, e.g. representing subgroups of wind turbines would also bewithin the scope of the present invention.

It is important that all stored data are preserved, which means thatdata when stored may not overwrite previously stored data of the datastructure.

The operational data comprises typically at least the power productionand the operational status of the wind turbine, but other data such astemperatures of various parts of the turbines, yawing angle, wind speedetc. may also form part of the operational data.

It is preferred that at least one of the correction routines produces aset of correction data being estimated data for the power production ofthe wind turbines.

Furthermore, the method may in a preferred embodiment furthermorecomprise means for allowing manual correction of the data. Thus, themethod may further comprise the steps of

-   -   activating a user input routine that allows for manual user        input of correction instructions,    -   receiving user input of correction instructions from a user        interface,    -   generating at least on set of manual correction data from said        correction instructions, and    -   storing said sets of manual correction data in thereto dedicated        parts of said data structure in said data storage means so that        all previous stored data are preserved.

It is furthermore advantageous that at least one of said reportscomprises credibility data based on the type and/or amount ofcorrections of the selected data from which the report is generated.

The present invention relates in a further aspect to a computer systemcomprising means for establishing at least temporarily data transmissionconnection with a plurality of wind turbines forming a wind power plantand having means for performing the above method as well as a computerprogramme product that is suitable for being run on a computer systemcomprising means for establishing at least temporarily data transmissionconnection with a plurality of wind turbines forming a wind power plantand enable said computer system to perform the method of the presentinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more apparent by describing in detailexample embodiments thereof with reference to the drawing in which:

FIG. 1 is a schematic drawing of a system for receiving and handlingdata from a plurality of wind turbine in accordance with an exampleembodiment of the present invention.

FIG. 2 is a flow chart illustrating a method for collecting andcorrecting operational data from a wind power plant by a computer devicein accordance with an example embodiment of the present invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

A preferred embodiment of the present invention is disclosed in thefollowing with reference to the accompanying drawings of which FIG. 1 isan overview of the wind power plant and the server infrastructure of thecomputer system and FIG. 2 is a flow chart of the data processingperformed in the computer system.

The Server Solution according to an embodiment of the present inventionis a SCADA system used for wind power plants. A wind power plantconsists of wind turbines, meteorology stations, substations and acontrol building. All units in at the power plant are loop connectedthrough fibre optical cables that meet up in the control building. Inthe control building a Small Business Server is installed with dedicatedsoftware for operation, monitoring and collection of historical datafrom the power plant.

All communication at the control building between Server and the Clientsis performed through a LAN, but is also possible to connect to theserver from a remote location through a dial-in connection (RAS-modem)

The Report Generator toolbox is a software product of the computersystem and consists of following components:

-   -   Report generator        -   For everyone who can generate a new report    -   Report archive        -   For everyone who can access generated reports    -   Shadow data editor        -   For on-site operators who is responsible for downtime            allocation, shadow-data integrity.    -   Profile administrator        -   For the administrator who is responsible for the            configuration of the system. This include event-list            allocation, calculation and raw data validation parameters

To be able to make report with maximum data integrity an automatic andmanual processing of the raw data is executed. Beside validation of thecollected data a number of different new values are calculated as well.

The following steps describes the work flow in using the ReportGenerator with reference to FIG. 2:

Step 1

All collected raw data from the turbines and other park units are storein a Windows SQL2000 database.

Step 2, 3 & 4

The shadow data tables consist of data generated based on raw data andcontractual parameters entered into the configuration table in theProfile Administrator module. The calculated new values are focusing onExpected Production used to estimate the complete power plantperformance.

Another very important set op values are the automatic and manualallocation of downtime. These values are use for documenting thecontractual availability.

All the raw and processed data are in general used for verifying theperformance of the power plant and by that the contractualresponsibilities. This makes the data processing subject to extensivefocus and high level of data transparency is required.

To meet the demand for data transparency, the software uses differentways of keeping an overview. The main features are:

-   -   Colour coding to separate the manipulated data from the raw        data.    -   Raw data is always read-only, which means that raw data never is        lost and always can be presented.    -   The system uses data priority instead of overwriting raw data.    -   e.g. The highest priority is always used for the reports:        -   Manual entered data, then auto-generated and finally raw            data. (Separate data table for each data set)    -   All contractual presented data have associated data integrity        reports.    -   When allocating downtime it is possible to add comments to all        auto-generated and manually edited allocations on a 10-minute        resolution.    -   The contractual profile can be locked including all performance        setting, contractual power curves and contractual availability        settings. A contractual profile cannot be edited without the        consent of all contractual parties.

Step 5 & 6

When data have been validated and manual edited the reports can begenerated, presented and stored as a table in the database.

Step 7 & 8

All generated reports/results are stored the Report Achieve whereeverybody with the right access can download and print the reports. Itis also possible to regenerate the individual report if the editedshadow data have been change further.

1. A method of collecting and correcting operational data from a windpower plant by a computer device, comprising the steps of: regularlyreceiving operational data from a plurality of wind turbine of said windpower plant, storing said operational data in a dedicated part of adimensionally ordered data structure in a data storage device associatedwith the computer device, performing a plurality of predefinedcorrection routines each producing a set of correction data, storingsaid sets of correction data in thereto dedicated parts of said datastructure in said data storage device so that all previous stored dataare preserved, and generating reports of a plurality of types, each typehaving a predefined set of rules for selecting data from said storeddata on which selected data the report type is based.
 2. A methodaccording to claim 1, wherein the operational data comprises at leastthe power production and the operational status of the wind turbine. 3.A method according to claim 1, wherein at least one of the correctionroutines produces a set of correction data being estimated data for thepower production of the wind turbines.
 4. A method according to claim 1,further comprising the steps of: activating a user input routine thatallows for manual user input of correction instructions, receiving userinput of correction instructions from a user interface, generating atleast on set of manual correction data from said correctioninstructions, and storing said sets of manual correction data in theretodedicated parts of said data structure in said data storage device sothat all previous stored data are preserved.
 5. A method according toclaim 1, wherein at least one of said reports comprises credibility databased on the type and/or amount of corrections of the selected data fromwhich the report is generated.
 6. A computer system comprising a devicefor establishing at least temporarily data transmission connection witha plurality of wind turbines forming a wind power plant and having meansfor performing the method of claim
 1. 7. A computer program product thatis suitable for being run on a computer system comprising a device forestablishing at least temporarily data transmission connection with aplurality of wind turbines forming a wind power plant and enable saidcomputer system to perform the method of claim
 1. 8. A computer systemcomprising a device for establishing at least temporarily datatransmission connection with a plurality of wind turbines forming a windpower plant and having means for performing the method of claim
 2. 9. Acomputer system comprising a device for establishing at leasttemporarily data transmission connection with a plurality of windturbines forming a wind power plant and having means for performing themethod of claim
 3. 10. A computer system comprising a device forestablishing at least temporarily data transmission connection with aplurality of wind turbines forming a wind power plant and having meansfor performing the method of claim
 4. 11. A computer system comprising adevice for establishing at least temporarily data transmissionconnection with a plurality of wind turbines forming a wind power plantand having means for performing the method of claim
 5. 12. A computerprogram product that is suitable for being run on a computer systemcomprising a device for establishing at least temporarily datatransmission connection with a plurality of wind turbines forming a windpower plant and enable said computer system to perform the method ofclaim
 2. 13. A computer program product that is suitable for being runon a computer system comprising a device for establishing at leasttemporarily data transmission connection with a plurality of windturbines forming a wind power plant and enable said computer system toperform the method of claim
 3. 14. A computer program product that issuitable for being run on a computer system comprising a device forestablishing at least temporarily data transmission connection with aplurality of wind turbines forming a wind power plant and enable saidcomputer system to perform the method of claim
 4. 15. A computer programproduct that is suitable for being run on a computer system comprising adevice for establishing at least temporarily data transmissionconnection with a plurality of wind turbines forming a wind power plantand enable said computer system to perform the method of claim 5.